4.2. Adding New Packages¶
PTXdist provides a huge amount of applications sufficient for the most embedded use cases. But there is still need for some fancy new packages. This section describes the steps and the background on how to integrate new packages into the project.
At first a summary about possible application types which PTXdist can handle:
- host type: This kind of package is built to run on the build host. Most of the time such a package is needed if another target-relevant package needs to generate some data. For example the glib package depends on its own to create some data. But if it is compiled for the target, it can’t do so. That’s why a host glib package is required to provide these utilities runnable on the build host. It sounds strange to build a host package, even if on the build host such utilities are already installed. But this way ensures that there are no dependencies regarding the build host system.
- target type: This kind of package is built for the target.
- cross type: This kind of package is built for the build host, but creates architecture specific data for the target.
- src-autoconf-prog: This kind of package is built for the target. It is intended for development, as it does not handle a released archive but a plain source project instead. Creating such a package will also create a small autotools based source template project on demand to give the developer an easy point to start. This template is prepared to build a single executable program. For further details refer section Creating an Executable Template.
- src-autoconf-lib: This kind of package is built for the target. It is intended for development, as it does not handle a released archive but a plain source project instead. Creating such a package will also create a small autotools/libtool based source template project on demand to give the developer an easy point to start. This template is prepared to build a single shared library. For further details refer section Creating a Library Template.
- src-autoconf-proglib: This kind of package is built for the target. It is intended for development, as it does not handle a released archive but a plain source project instead. Creating such a package will also create a small autotools/libtool based template project on demand to give the developer an easy point to start. This template is prepared to build a single shared library and a single executable program. The program will be linked against the shared library. For further details refer section Creating an Executable with a Library Template.
- file: This kind of package is intended to add a few simple files into the build process. We assume these files do not need any processing, they are ready to use and must only be present in the build process or at run-time (HTML files for example). Refer to the section Adding Binary Only Files for further details on how to use it.
- src-make-prog: This kind of package is built for the target. It’s intended for development, as it does not handle a released archive but a plain source project instead. Creating such a package will also create a simple makefile-based template project the developer can use as a starting point for development.
- src-cmake-prog: This kind of package is built for the target. It’s intended for developments based on the cmake buildsystem. Various projects are using cmake instead of make and can be built with this package type. PTXdist will prepare it to compile sources in accordance to the target libraries and their settings. Creating such a package will also create a simple template project to be used as a starting point for development.
- src-qmake-prog: This kind of package is built for the target. It’s intended for developments based on the qmake buildsystem. If the developer is going to develop a QT based application, this rule is prepared to compile sources in accordance to the target libraries and their settings. Creating such a package will also create a simple template project to be used as a starting point for development.
- src-meson-prog: This kind of package is built for the target. It’s intended for developments based on the meson buildsystem. Various projects are using meson today and can be built with this package type. PTXdist will prepare it to compile sources in accordance to the target libraries and their settings. Creating such a package will also create a simple template project to be used as a starting point for development.
- font: This package is a helper to add X font files to the root filesystem. This package does not create an additional IPKG, instead it adds the font to the existing font IPKG. This includes the generation of the directory index files, required by the Xorg framework to recognize the font file.
- src-linux-driver: This kind of package builds an out of tree kernel driver. It also creates a driver template to give the developer an easy point to start.
- kernel: PTXdist comes with the ability to handle one kernel in its platform. This type of package enables us to handle more than one kernel in the project.
- barebox: PTXdist comes with the ability to handle one bootloader in its platform. This type of package enables us to handle more than one bootloader in the project.
- image-tgz: This kind of package creates a tar ball from a list of packages. It is often uses as an input for other image packages.
- image-genimage: This kind of package can handle all kind of image generation for almost every target independent of its complexity.
- blspec-entry: PTXdist comes with the ability to handle one bootspec in its platform. This type of package enables us to handle more than one bootspec in the project.
Rule File Creation¶
To create such a new package, we create a project local
directory first. Then we run
$ ptxdist newpackage <package type>
If we omit the <
package type>, PTXdist will list all available
In our first example, we want to add a new target type archive package. When running the
$ ptxdist newpackage target
command, PTXdist asks a few questions about this package. This information is the basic data PTXdist must know about the package.
ptxdist: creating a new 'target' package: ptxdist: enter package name.......: foo ptxdist: enter version number.....: 1.1.0 ptxdist: enter URL of basedir.....: http://www.foo.com/download/src ptxdist: enter suffix.............: tar.gz ptxdist: enter package author.....: My Name <firstname.lastname@example.org> ptxdist: enter package section....: project_specific
What we have to answer:
- package name: As this kind of package handles a source archive,
the correct answer here is the basename of the archive’s file name.
If its full name is
foois the basename to enter here.
- version number: Most source archives are using a release or
version number in their file name. If its full name is
1.1.0is the version number to enter here.
- URL of basedir: This URL tells PTXdist where to download the
source archive from the web (if not already done). If the full URL to
download the archive is
http://www.foo.com/download/src/foo-1.1.0.tar.gz, the basedir part
http://www.foo.com/download/srcis to be entered here.
- suffix: Archives are using various formats for distribution.
PTXdist uses the suffix entry to select the matching extraction
tool. If the archive’s full name is
tar.gzis the suffix to enter here.
- package author: If we intend to contribute this new package to
PTXdist mainline, we should add our name here. This name will be used
in the copyright note of the rule file and will also be added to the
generated ipkg. When you run
ptxdist setupprior to this call, you can enter your name and your email address, so PTXdist will use it as the default (very handy if you intend to add many new packages).
- package section: We can enter here the menu section name where our new package menu entry should be listed. In the first step we can leave the default name unchanged. It’s a string in the menu file only, so changing it later on is still possible.
Make it Work¶
Generating the rule file is only one of the required steps to get a new package. The next steps to make it work are to check if all stages are working as expected and to select the required parts to get them installed in the target root filesystem. Also we must find a reasonable location where to add our new menu entry to configure the package.
The generated skeleton starts to add the new menu entry in the main
configure menu (if we left the section name unchanged). Running
ptxdist menuconfig will show it on top of all other menus entries.
To be able to implement and test all the other required steps for adding a new package, we first must enable the package for building. (Fine tuning the menu can happen later on.)
The rule file skeleton still lacks some important information. Let’s
take a look into some of the top lines of the generated rule file
FOO_VERSION := 1.1.0 FOO_MD5 := FOO := foo-$(FOO_VERSION) FOO_SUFFIX := tar.gz FOO_URL := http://www.foo.com/download/src/$(FOO).$(FOO_SUFFIX) FOO_SOURCE := $(SRCDIR)/$(FOO).$(FOO_SUFFIX) FOO_DIR := $(BUILDDIR)/$(FOO) FOO_LICENSE := unknown
We can find these lines with different content in most or all of the other rule files PTXdist comes with. Up to the underline character is always the package name and after the underline character is always PTXdist specific. What does it mean:
*_VERSIONbrings in the version number of the release and is used for the download and IPKG/OPKG package generation.
*_MD5to be sure the correct package has been downloaded, PTXdist checks the given MD5 sum against the archive content. If both sums do not match, PTXdist rejects the archive and fails the currently running build.
*_SUFFIXdefines the archive type, to make PTXdist choosing the correct extracting tool.
*_URLdefines the full qualified URL into the web for download. If alternative download locations are known, they can be listed in this variable, delimiter character is the space.
*_SOURCEtells PTXdist where to store the downloaded package.
*_DIRpoints to the directory this package will be built later on by PTXdist.
*_LICENSEenables the user to get a list of licenses she/he is using in her/his project (licenses of the enabled packages).
After enabling the menu entry, we can start to check the get and extract stages, calling them manually one after another.
The shown commands below expect that PTXdist downloads the
archives to a global directory named
global_src. This is not the
default setting, but we recommend to use a global directory to share all
archives between PTXdist based projects. Advantage is every download
happens only once. Refer to the
setup command PTXdist provides.
$ ptxdist get foo --------------------------- target: foo-1.1.0.tar.gz --------------------------- --2009-12-21 10:54:45-- http://www.foo.com/download/src/foo-1.1.0.tar.gz Length: 291190 (284K) [application/x-gzip] Saving to: `/global_src/foo-1.1.0.tar.gz.XXXXOGncZA' 100%[======================================>] 291,190 170K/s in 1.7s 2009-12-21 10:54:48 (170 KB/s) - `/global_src/foo-1.1.0.tar.gz' saved [291190/291190]
This command should start to download the source archive. If it fails, we should check our network connection, proxy setup or if the given URL in use is correct.
Sometimes we do not know the content of all the other variables in the rule file. To get an idea what content a variable has, we can ask PTXdist about it:
$ ptxdist print FOO_URL http://www.foo.com/download/src/foo-1.1.0.tar.gz
The next step would be to extract the archive. But as PTXdist checks the
MD5 sum in this case, this step will fail, because the
variable is still empty. Let’s fill it:
$ md5sum /global_src/foo-1.1.0.tar.gz 9a09840ab775a139ebb00f57a587b447
This string must be assigned to the FOO_MD5 in our new
FOO_MD5 := 9a09840ab775a139ebb00f57a587b447
We are now prepared for the next step:
$ ptxdist extract foo ----------------------- target: foo.extract ----------------------- extract: archive=/global_src/foo-1.1.0.tar.gz extract: dest=/home/jbe/my_new_prj/build-target PATCHIN: packet=foo-1.1.0 PATCHIN: dir=/home/jbe/my_new_prj/build-target/foo-1.1.0 PATCHIN: no patches for foo-1.1.0 available Fixing up /home/jbe/my_new_prj/build-target/foo-1.1.0/configure finished target foo.extract
In this example we expect an autotoolized source package. E.g. to
prepare the build, the archive comes with a
configure script. This
is the default case for PTXdist. So, there is no need to modify the rule
file and we can simply run:
$ ptxdist prepare foo ----------------------- target: foo.prepare ----------------------- [...] checking build system type... i686-host-linux-gnu checking host system type... arm-v5te-linux-gnueabi checking whether to enable maintainer-specific portions of Makefiles... no checking for a BSD-compatible install... /usr/bin/install -c checking whether build environment is sane... yes checking for a thread-safe mkdir -p... /bin/mkdir -p checking for gawk... gawk checking whether make sets $(MAKE)... yes checking for arm-v5te-linux-gnueabi-strip... arm-v5te-linux-gnueabi-strip checking for arm-v5te-linux-gnueabi-gcc... arm-v5te-linux-gnueabi-gcc checking for C compiler default output file name... a.out [...] configure: creating ./config.status config.status: creating Makefile config.status: creating ppa_protocol/Makefile config.status: creating config.h config.status: executing depfiles commands finished target foo.prepare
At this stage things can fail:
- A wrong or no MD5 sum was given
configurescript is not cross compile aware
- The package depends on external components (libraries for example)
configure script is not cross compile aware, we are out of
luck. We must patch the source archive in this case to make it work.
Refer to the section Modifying Autotoolized Packages on how to use
PTXdist’s features to simplify this task.
If the package depends on external components, these components might
be already part of PTXdist. In this case we just have to add this
dependency into the menu file and we are done. But if PTXdist cannot
fulfill this dependency, we also must add it as a separate package
If the prepare stage has finished successfully, the next step is to compile the package.
$ ptxdist compile foo ----------------------- target: foo.compile ----------------------- make: Entering directory `/home/jbe/my_new_prj/build-target/foo-1.1.0' make all-recursive make: Entering directory `/home/jbe/my_new_prj/build-target/foo-1.1.0' make: Entering directory `/home/jbe/my_new_prj/build-target/foo-1.1.0' [...] make: Leaving directory `/home/jbe/my_new_prj/build-target/foo-1.1.0' make: Leaving directory `/home/jbe/my_new_prj/build-target/foo-1.1.0' make: Leaving directory `/home/jbe/my_new_prj/build-target/foo-1.1.0' finished target foo.compile
At this stage things can fail:
- The build system is not cross compile aware (it tries to execute just created target binaries for example)
- The package depends on external components (libraries for example)
not detected by
- Sources are ignoring the endianness of some architectures or using
header files from the build host system (from
- The linker uses libraries from the build host system (from
/usr/libfor example) by accident
In all of these cases we must patch the sources to make them work. Refer to section Patching Packages on how to use PTXdist’s features to simplify this task.
In this example we expect the best case: everything went fine, even for cross compiling. So, we can continue with the next stage: install
$ ptxdist install foo ----------------------- target: foo.install ----------------------- make: Entering directory `/home/jbe/my_new_prj/build-target/foo-1.1.0' make: Entering directory `/home/jbe/my_new_prj/build-target/foo-1.1.0' make: Entering directory `/home/jbe/my_new_prj/build-target/foo-1.1.0' test -z "/usr/bin" || /bin/mkdir -p "/home/jbe/my_new_prj/build-target/foo-1.1.0/usr/bin" /usr/bin/install -c 'foo' '/home/jbe/my_new_prj/build-target/foo-1.1.0/usr/bin/foo' make: Leaving directory `/home/jbe/my_new_prj/build-target/foo-1.1.0' make: Leaving directory `/home/jbe/my_new_prj/build-target/foo-1.1.0' make: Leaving directory `/home/jbe/my_new_prj/build-target/foo-1.1.0' finished target foo.install ---------------------------- target: foo.install.post ---------------------------- finished target foo.install.post
This install stage does not install anything to the target root filesystem. It is mostly intended to install libraries and header files other programs should link against later on.
The last stage – targetinstall – is the one that defines the package’s
components to be forwarded to the target’s root filesystem. Due to the
absence of a generic way, this is the task of the developer. So, at this
point of time we must run our favourite editor again and modify our new
The skeleton for the targetinstall stage looks like this:
# ---------------------------------------------------------------------------- # Target-Install # ---------------------------------------------------------------------------- $(STATEDIR)/foo.targetinstall: @$(call targetinfo) @$(call install_init, foo) @$(call install_fixup, foo,PACKAGE,foo) @$(call install_fixup, foo,PRIORITY,optional) @$(call install_fixup, foo,VERSION,$(FOO_VERSION)) @$(call install_fixup, foo,SECTION,base) @$(call install_fixup, foo,AUTHOR,"My Name <email@example.com>") @$(call install_fixup, foo,DEPENDS,) @$(call install_fixup, foo,DESCRIPTION,missing) @$(call install_copy, foo, 0, 0, 0755, $(FOO_DIR)/foobar, /dev/null) @$(call install_finish, foo) @$(call touch)
The “header” of this stage defines some information IPKG needs. The
important part that we must modify is the call to the
macro (refer to section Rule File Macro Reference for more details
about this kind of macros). This call instructs PTXdist to include the
given file (with UID, GID and permissions) into the IPKG, which means to
install this file to the target’s root filesystem.
From the previous install stage we know this package installs an
foo to location
/usr/bin. We can do the same
for our target by changing the install_copy line to:
@$(call install_copy, foo, 0, 0, 0755, $(FOO_DIR)/foo, /usr/bin/foo)
To check it, we just run:
$ ptxdist targetinstall foo ----------------------------- target: foo.targetinstall ----------------------------- install_init: preparing for image creation... install_init: @ARCH@ -> i386 ... done install_init: preinst not available install_init: postinst not available install_init: prerm not available install_init: postrm not available install_fixup: @PACKAGE@ -> foo ... done. install_fixup: @PRIORITY@ -> optional ... done. install_fixup: @VERSION@ -> 1.1.0 ... done. install_fixup: @SECTION@ -> base ... done. install_fixup: @AUTHOR@ -> "My Name <me\@my-org.com>" ... done. install_fixup: @DESCRIPTION@ -> missing ... done. install_copy: src=/home/jbe/my_new_prj/build-target/foo-1.1.0/foo dst=/usr/bin/foo owner=0 group=0 permissions=0755 xpkg_finish: collecting license (unknown) ... done. xpkg_finish: creating ipkg package ... done. finished target foo.targetinstall ---------------------------------- target: foo.targetinstall.post ---------------------------------- finished target foo.targetinstall.post
After this command, the target’s root filesystem contains a file called
/usr/bin/foo owned by root, its group is also root and everyone has
execution permissions, but only the user root has write permissions.
One last task of this port is still open: A reasonable location for
the new menu entry in PTXdist’s menu hierarchy. PTXdist arranges its
menus on the meaning of each package. Is it a network related tool? Or
a scripting language? Or a graphical application?
Each of these global meanings has its own submenu, where we can add
our new entry to. We just have to edit the head of our new menu file
./rules/foo.in to add it to a specific global menu. If our new
package is a network related tool, the head of the menu file should
We can grep through the other menu files from the PTXdist main
rules/ directory to get an idea what section names are
rules/ $ find . -name \*.in | xargs grep "## SECTION" ./acpid.in:## SECTION=shell_and_console ./alsa-lib.in:## SECTION=system_libraries ./alsa-utils.in:## SECTION=multimedia_sound ./apache2.in:## SECTION=networking ./apache2_mod_python.in:## SECTION=networking [...] ./xkeyboard-config.in:## SECTION=multimedia_xorg_data ./xorg-app-xev.in:## SECTION=multimedia_xorg_app ./xorg-app-xrandr.in:## SECTION=multimedia_xorg_app ./host-eggdbus.in:## SECTION=hosttools_noprompt ./libssh2.in:## SECTION=networking
Porting a new package to PTXdist is (almost) finished now.
To check it right away, we simply run these two commands:
$ ptxdist clean foo rm -rf /home/jbe/my_new_prj/state/foo.* rm -rf /home/jbe/my_new_prj/packages/foo_* rm -rf /home/jbe/my_new_prj/build-target/foo-1.1.0 $ ptxdist targetinstall foo [...]
Discover somehow hidden dependencies with one more last check!
Up to this point all the development of the new package was done in an already built BSP. Doing so sometimes somehow hidden dependencies cannot be seen: everything seems fine, the new package builds always successfully and the results are working on the target.
So to check for this kind of dependencies there is still one more final check to do (even if its boring and takes time):
$ ptxdist clean [...] $ ptxdist targetinstall foo [...]
This will re-start with a clean BSP and builds exactly the new package and its (known) dependencies. If this builds successfully as well we are really done with the new package.
Some Notes about Licenses¶
The already mentioned rule variable
FOO_LICENSE in our
example) is very important and must be filled by the developer of the package.
Many licenses bring in obligations using the corresponding package (attribution
for example). To make life easier for everybody the license for a package must
be provided. SPDX license identifiers unify the license names and are used
in PTXdist to identify license types and obligations.
If a package comes with more than one license, all of their SPDX identifiers
must be listed and connected with the keyword
AND. If your package comes
with GPL-2.0 and LGPL-2.1 licenses, the definition should look like this:
FOO_LICENSE := GPL-2.0 AND LGPL-2.1
One specific obligation cannot be detected examining the SPDX license identifiers
by PTXdist: the license choice. In this case all licenses of choice must be
listed and connected by the keyword
If, for example, your obligation is to select one of the licenses GPL-2.0 or
*_LICENSE variable should look like this:
FOO_LICENSE := GPL-2.0 OR GPL-3.0
SPDX License Identifiers¶
A list of SPDX license identifiers can be found here:
Help to Detect the Correct License¶
License identification isn’t trivial. A help in doing so can be the following repository and its content. It contains a list of known licenses based on their SPDX identifier. The content is without formatting to simplify text search.
Advanced Rule Files¶
The previous example on how to create a rule file sometimes works as shown above. But most of the time source archives are not that simple. In this section we want to give the user a more detailed selection how the package will be built.
Adding Static Configure Parameters¶
configure scripts of various source archives provide additional
parameters to enable or disable features, or to configure them in a
We assume the
configure script of our
foo example (refer to
section Rule File Creation) supports two additional parameters:
- –enable-debug: Make the program more noisy. It’s disabled by default.
- –with-bar: Also build the special executable bar. Building this executable is also disabled by default.
We now want to forward these options to the
configure script when it
runs in the prepare stage. To do so, we must again open the rule file
with our favourite editor and navigate to the prepare stage entry.
PTXdist uses the variable
FOO_CONF_OPT as the list of parameters to
be given to
Currently this variable is commented out and defined to:
# FOO_CONF_OPT := $(CROSS_AUTOCONF_USR)
CROSS_AUTOCONF_USR is predefined by PTXdist and
contains all basic parameters to instruct
configure to prepare for a
cross compile environment.
To use the two additional mentioned
configure parameters, we comment
in this line and supplement this expression as follows:
FOO_CONF_OPT := \ $(CROSS_AUTOCONF_USR) \ --enable-debug \ --with-bar
We recommend to use this format with each parameter on a line of its own. This format is easier to read and a diff shows more exactly any change.
To do a fast check if this addition was successful, we run:
$ ptxdist print FOO_CONF_OPT --prefix=/usr --sysconfdir=/etc --host=arm-v5te-linux-gnueabi --build=i686-host-linux-gnu --enable-debug --with-bar
It depends on the currently selected platform and its architecture what content this variable will have. The content shown above is an example for a target.
Or re-build the package with the new settings:
$ ptxdist drop foo prepare $ ptxdist targetinstall foo
Adding Dynamic Configure Parameters¶
Sometimes it makes sense to add this kind of parameters on demand only;
especially a parameter like
--enable-debug. To let the user decide
if this parameter is to be used or not, we must add a menu entry. So,
let’s expand our menu. Here is its current content:
## SECTION=project_specific config FOO tristate prompt "foo" help FIXME
We’ll add two menu entries, one for each optional parameter we want to
add on demand to the
## SECTION=project_specific config FOO tristate prompt "foo" help FIXME if FOO config FOO_DEBUG bool prompt "add debug noise" config FOO_BAR bool prompt "build bar" endif
Always follow the rule to extend the base name by a suboption name as the trailing part of the variable name. This gives PTXdist the ability to detect a change in the package’s settings (via menuconfig) to force its rebuild on demand.
To make usage of the new menu entries, we must check them in the rule file and add the correct parameters:
# # autoconf # FOO_CONF_OPT := \ $(CROSS_AUTOCONF_USR) \ --$(call ptx/endis, PTXCONF_FOO_DEBUG)-debug \ --$(call ptx/wwo, PTXCONF_FOO_BAR)-bar
Please note the leading
PTXCONF_ for each define. While Kconfig is
FOO_BAR, the rule file must use
Refer Rule File Macro Reference for further
details about these special kind of option macros (e.g.
It is a good practice to always add both settings, e.g.
even if this is the default case. Sometimes
configure tries to guess
something and the binary result might differ depending on the build
order. For example some kind of package would also build some X related
tools, if X libraries are found. In this case it depends on the build
order, if the X related tools are built or not. All the autocheck
features are problematic here. So, if we do not want
guess its settings we must disable everything we do not want.
To support this process, PTXdist supplies a helper script, located at
/path/to/ptxdist/scripts/configure-helper.py that compares the configure
output with the settings from
$ /opt/ptxdist-2017.06.0/scripts/configure-helper.py -p libsigrok --- rules/libsigrok.make +++ libsigrok-0.5.0 @@ -4,3 +4,74 @@ --libdir=/usr/lib --build=x86_64-host-linux-gnu --host=arm-v7a-linux-gnueabihf + --enable-warnings=min|max|fatal|no + --disable-largefile + --enable-all-drivers + --enable-agilent-dmm [...] + --enable-ruby + --enable-java + --without-libserialport + --without-libftdi + --without-libusb + --without-librevisa + --without-libgpib + --without-libieee1284 + --with-jni-include-path=DIR-LIST
In this example, many configure options from libsigrok (marked with
are not yet present in
LIBSIGROK_CONF_OPT and must be added, possibly also
by providing more dynamic options in the package definition.
If some parts of a package are built on demand only, they must also be installed on demand only. Besides the prepare stage, we also must modify our targetinstall stage:
@$(call install_copy, foo, 0, 0, 0755, $(FOO_DIR)/foo, /usr/bin/foo) ifdef PTXCONF_FOO_BAR @$(call install_copy, foo, 0, 0, 0755, $(FOO_DIR)/bar, /usr/bin/bar) endif @$(call install_finish, foo) @$(call touch)
Now we can play with our new menu entries and check if they are working as expected:
$ ptxdist menuconfig $ ptxdist targetinstall foo
Whenever we change a FOO related menu entry, PTXdist should detect it and re-build the package when a new build is started.
Managing External Compile Time Dependencies¶
While running the prepare stage, it could happen that it fails due to a missing external dependency.
checking whether zlib exists....failed
In this example, our new package depends on the compression library
zlib. PTXdist comes with a target zlib. All we need to do in this
case is to declare that our new package foo depends on zlib. This
kind of dependency is managed in the menu file of our new package by
simply adding the
select ZLIB line. After this addition our menu
file looks like:
## SECTION=project_specific config FOO tristate select ZLIB prompt "foo" help FIXME if FOO config FOO_DEBUG bool prompt "add debug noise" config FOO_BAR bool prompt "build bar" endif
PTXdist now builds the zlib first and our new package thereafter.
Refer Controlling Package Dependencies in more Detail for more specific dependency description.
Managing External Compile Time Dependencies on Demand¶
It is good practice to add only those dependencies that are really
required for the current configuration of the package. If the package
provides the features foo and bar and its
switches to enable/disable them independently, we can also add
dependencies on demand. Let’s assume feature foo needs the compression
library libz and bar needs the XML2 library libxml2. These
libraries are only required at run-time if the corresponding feature is
enabled. To add these dependencies on demand, the menu file looks like:
## SECTION=project_specific config FOO tristate select ZLIB if FOO_FOO select LIBXML2 if FOO_BAR prompt "foo" help FIXME if FOO config FOO_DEBUG bool prompt "add debug noise" config FOO_FOO bool prompt "build foo" config FOO_BAR bool prompt "build bar" endif
Do not add these
select statements to the corresponding menu entry.
They must belong to the main menu entry of the package to ensure that
the calculation of the dependencies between the packages is done in a
Managing External Runtime Dependencies¶
Some packages are building all of their components and also installing them into the target’s sysroot. But only their targetinstall stage decides which parts are copied to the root filesystem. So, compiling and linking of our package will work, because everything required is found in the target’s sysroot.
In our example there is a hidden dependency to the math library
libm. Our new package was built successfully, because the linker was
able to link our binaries against the
libm from the toolchain. But
in this case the
libm must also be available in the target’s root
filesystem to fulfil the run-time dependency: We have to force PTXdist to
libm is part of the glibc package, but is not
installed by default (to keep the root filesystem small). So, it does
not help to select the
GLIBC symbol, to get a
libm at run-time.
The correct solution here is to add a
select LIBC_M to our menu
file. With all the additions above it now looks like:
## SECTION=project_specific config FOO tristate select ZLIB if FOO_FOO select LIBXML2 if FOO_BAR select LIBC_M prompt "foo" help FIXME if FOO config FOO_DEBUG bool prompt "add debug noise" config FOO_FOO bool prompt "build foo" config FOO_BAR bool prompt "build bar" endif
There are other packages around, that do not install everything by
default. If our new package needs something special, we must take a look
into the menu of the other package how to force the required components
to be installed and add the corresponding
selects to our own menu
file. In this case it does not help to enable the required parts in our
project configuration, because this has no effect on the build order!
Managing Plain Makefile Packages¶
Many packages are still coming with a plain
Makefile. The user has
to adapt it to make it work in a cross compile environment as well.
PTXdist can also handle this kind of packages. We only have to specify
a special prepare and compile stage.
Such packages often have no special need for any kind of preparation. In this we must instruct PTXdist to do nothing in the prepare stage:
FOO_CONF_TOOL := NO
To compile the package, we can use
make’s feature to overwrite
variables used in the
Makefile. With this feature we can still use
Makefile but with our own (cross compile) settings.
Most of the time the generic compile rule can be used, only a few
settings are required. For a well defined
Makefile it is sufficient to
set up the correct cross compile environment for the compile stage:
FOO_MAKE_ENV := $(CROSS_ENV)
make will be called in this case with:
$(FOO_MAKE_ENV) $(MAKE) -C $(FOO_DIR) $(FOO_MAKE_OPT)
So, in the rule file only the two variables
FOO_MAKE_OPT must be set, to forward the required settings to the
package’s buildsystem. If the package cannot be built in parallel, we
can also add the
FOO_MAKE_PAR := NO.
YES is the default.
Managing CMake/QMake/Meson Packages¶
Building packages that use
meson is much like
building packages with an autotools based buildsystem. We need to specify
the configuration tool:
FOO_CONF_TOOL := cmake
FOO_CONF_TOOL := qmake
FOO_CONF_TOOL := meson
And provide the correct configuration options. The syntax is different so
PTXdist provides additional macros to simplify configurable features.
cmake the configuration options typically look like this:
FOO_CONF_OPT := \ $(CROSS_CMAKE_USR) \ -DBUILD_TESTS:BOOL=OFF \ -DENABLE_BAR:BOOL=$(call ptx/onoff, PTXCONF_FOO_BAR)
qmake the configuration options typically look like this:
FOO_CONF_OPT := \ $(CROSS_QMAKE_OPT) \ PREFIX=/usr
meson the configuration options typically look like this:
FOO_CONF_OPT := \ $(CROSS_MESON_USR) \ -Dbar=$(call ptx/truefalse,PTXCONF_FOO_BAR)
Please note that currently only host and target
and only target
qmake packages are supported.
Managing Python Packages¶
As with any other package, the correct configuration tool must be selected for Python packages:
FOO_CONF_TOOL := python
For Python3 packages the value must be
No Makefiles are used when building Python packages so the usual
make install for the compile and install stages cannot be used.
PTXdist will call
python setup.py build and
python setup.py install
FOO is still the name of our example package. It must be replaced by the real package name.
There can be various reasons why a package must be patched:
- Package is broken for cross compile environments
- Package is broken within a specific feature
- Package is vulnerable and needs some fixes
- or anything else (this case is the most common one)
Ideally, those problems should be addressed in the original project, so any patches you add to your BSP or to PTXdist should also be submitted upstream. The upstream project can often provide better feedback, they can integrate your patch into a new release, and also maintain your changes as part of the project. This way we make sure that all advantages of the open source idea work for us; and your patch can be removed again later when a new release of the project is integrated into your BSP or into PTXdist.
PTXdist handles patching automatically.
After extracting the archive of a package, PTXdist checks for the existence of
a patch directory named like its
<PKG>_PATCHES variable, or, if this variable
is not set, like its
The patch directory is then searched in all locations listed by the
PTXDIST_PATH_PATCHES variable, and the first one found is used.
Take an exemplary package
foo with version
FOO will have the value
foo-1.1.0, so PTXdist will look for
a patch directory named
foo-1.1.0 in the following locations:
- the current layer:
- project (
- platform (
- project (
- any base layers, applying the same search order as above for each layer recursively
- ptxdist (
The patches from the first location found are used. Note: Due to this search order, a PTXdist project can replace global patches from the PTXdist installation. This can be useful if a project sticks to a specific PTXdist revision but fixes from a more recent revision of PTXdist should be used.
PTXdist uses the utilities git, patch or quilt to work with patches or patch series. We recommend git, as it can manage patch series in a very easy way.
Creating a Patch Series for a Package¶
To create a patch series for the first time, we can run the following steps. We are still using our foo-1.1.0 example package here:
We create a special directory for the patch series in the local project directory:
$ mkdir -p patches/foo-1.1.0
PTXdist expects a
series file in the patch directory and at least
one patch. Otherwise it fails. Due to the fact that we do not have any
patch content yet, we’ll start with a dummy entry in the
and an empty
$ touch patches/foo-1.1.0/dummy $ echo dummy > patches/foo-1.1.0/series
Next is to extract the package (if already done, we must remove it first):
$ ptxdist extract foo
This will extract the archive and create a symbolic link in the build
directory pointing to our local patch directory. Working this way will
ensure that we do not lose our created patches if we enter
ptxdist clean foo by accident. In our case the patches are still
patches/foo-1.1.0 and can be used the next time we
extract the package again.
All we have to do now is to do the modification we need to make the
package work. We change into the build directory and use quilt to
create new patches, add files to respective patches, modify these files
and refresh the patches to save our changes.
See the quilt documentation (
man 1 quilt) for more information.
For patches that are intended for PTXdist upstream use the git workflow described below to get proper patch headers.
Create the patch directory like above for quilt, but only add an empty series file:
$ mkdir -p patches/foo-1.1.0 $ touch patches/foo-1.1.0/series
Then extract the package with an additional command line switch:
$ ptxdist --git extract foo
The empty series file makes PTXdist create a Git repository in the respective package build directory, and import the package source as the first commit.
Optionally, you can enable the setting Developer Options → use git to apply patches in ptxdist setup to get this behaviour as a default for every package. However, note that this setting is meant for development only, and can lead to failures – some packages try to determine if they are being compiled from a Git source tree, and behave differently in that case.
Then you can change into the package build directory
patch the required source files,
and make Git commits on the way.
The Git history should now look something like this:
$ git log --oneline --decorate * df343e821851 (HEAD -> master) Makefile: don't build the tests * 65a360c2bd60 strfry.c: frobnicate the excusator * fdc315f6844c (tag: foobar-1.1.0, tag: base) initial commit
git ptx-patches to transform those Git commits into the patch
series in the
This way they don’t get lost when cleaning the package.
PTXdist will only create a Git repository for packages with
patches. To use Git to generate the first patch, create an empty series
patches/foobar-1.1.0/series before extracting the packages. This
will tell PTXdist to use Git anyways and
git ptx-patches will put the
Both approaches (Git and quilt) are not suitable for modifying files that are autogenerated in autotools-based buildsystems. Refer to the section Modifying Autotoolized Packages on how PTXdist can handle this special task.
Adding More Patches to a Package¶
If we want to add more patches to an already patched package, we can use nearly the same way as creating patches for the first time. But if the patch series comes from the PTXdist main installation, we do not have write permissions to these directories (do NEVER work on the main installation directories, NEVER, NEVER, NEVER). Due to the search order in which PTXdist searches for patches for a specific package, we can copy the global patch series to our local project directory. Now we have the permissions to add more patches or modify the existing ones. Also quilt and git are our friends here to manage the patch series.
If we think that our new patches are valuable also for others, or they fix an error, it could be a good idea to send these patches to PTXdist mainline, and to the upstream project too.
Modifying Autotoolized Packages¶
Autotoolized packages are very picky when automatically generated files get patched. The patch order is very important in this case and sometimes it even fails and nobody knows why.
To improve a package’s autotools-based build system, PTXdist comes with
its own project local autotools to regenerate the autotools template
files, instead of patching them. With this feature, only the template
files must be patched, the required
configure script and the
Makefile.in files are regenerated in the final stages of the
This feature works like the regular patching mechanism. The only
difference is the additional
autogen.sh file in the patch directory.
If it exists and has execution permissions, it will be called after the
package was patched (while the extract stage is running).
Its content depends on developer needs; for the most simple case the content can be:
#!/bin/bash aclocal $ACLOCAL_FLAGS libtoolize \ --force \ --copy autoreconf \ --force \ --install \ --warnings=cross \ --warnings=syntax \ --warnings=obsolete \ --warnings=unsupported
In this way not yet autotoolized package can be autotoolized. We
just have to add the common autotool template files (
Makefile.am for example) via a patch series to the package
source and the
autogen.sh to the patch directory.